Improved flask for molding bath-tubs



Unirse STATESL PATENT OFFICE.'

JNO. DEMAREST, GFMGTT HAVEN, NEW YORK, SSl'G-NOR TO THE J. In MOTT IRON VORKS.

lMPROVED FLSK FOR MOLDiNG BATH-TUBS.

bpecitication forming part of Letters Patent No. l 3,5 ld, dated August 2*, lb.

To aZZ whom it may concern.-

Be it known that I, JOHN DEMAREsT, of Mott Haven, Westchester county, and State of New York, have invented certain new and useful improvements in three part liasks' taken at the lines A a and B b of Fig. 1.

- The same letters indicate like parts in all the figures.

The molding of bath-tubs and other large and thin hollow articles requiring three-part flasks has heretofore been attended with serious ditlculties. The three parts or sections ot' the liask are rectangular wooden frames,- the sides of which readily yield to pressure, and the Whole mold when complete is very heavy, so that in the process of molding and in moving the flask the sides yield, so that the accuracy ofthe inold is destroyed, and the article when cast is too thin and weak in some parts and too thick and heavy in others, and such inaccuracies in the mold,if not discovered before casting, cannot be remedied without remolding. Again, the sand forming the sides of the mold, particularly'where it overhangs by reason of the inclination or curvature of the sides, is liable to eavein, asitis termed, 'lhus destroying` the mold in whole or in part.

The object ol' my invention is to avoid these inconveniences; and it consists in connecting the sides of the drag or first sect-ion of the flask and the cope or third section of the llask, or either, with a cross brace, bar, or bars, to prevent them from yielding to any pressure or strain to which they may bev subjected, in combination with clamps and clamp-screws attached to the sides ol the drag and cope, or either, and embracing the cheek orv second section ot' the llask, which is not braced, so that the sides ot' this second section can be thus held and adjusted at pleasure by the clamp-screws or their equivalents, and thus effectually prevent the flask from being strained to change the form of the mold after it has been completed, while at the same time the sides can be adjusted to equalize the sides ot the mold, if from any cause it should be found that one side of the mold is of greater thickness than the other; and my s aid invention consists in preventing the sides of .the sand mold inside of the flask from caving in, as it is termed, by recessing or cutting out the upper edge of the vertical wings which project inside of the cheek or second section of t-he flask, leaving the upper edge near the inner' edge the highest, so that the union of the sand over these recessed edges of the wings will cffectually sustain the sides of the molds and prevent them from caving in.

, In the accompanying drawings, a represents the drag or lower section of the llask, which is to be filled and rammed down to receive the pattern of the bath-tub b or other article with the upper edge downward. Across the middle of the length there is an iron brace-bar, c, firmly secured to the sides to keep them from being strained apart by any forcey applied in side or outside. This brace may be ot' any desired breadth; or sever-.il of them may be inserted at dilterent portions of the length; and to the outside are secured iron clamps d d, that extend above the upper edge, and there provided with clamp-screws e e. The cheek or middle section, 1', ol` the mold is formed, as usual, of two side boards, 0 y, and two end boards, h l1, and lits onto the upper edge of the drag a and within theclamps d d, so that the ends ot' the clampserews l: c shall bear against and hold the sides y g to prevent them from yielding to the pressure within. The cope 'i or third section is also a rectangular frame, as usual, 'lilted to rest on the upper edge ofthe second sectiomand connected therewith by hooks j, as the second section is connected with-the lrst. The sides of the cope, like the sides of the drag,are firmly connected together by a cross brace-bant', placed across the middle ofthe length, and,if dcsired,others may be placed at ditl'erent parts ot' the length. The sides are provided outside with clamps l Z, lapping over the sides ol' the second section, and .provided with elampscrews m m.. The opposite sides of the lirst and ot' the third sed e letra tions being,r thus bound together by the crossbraces,and provided with clamps and clampscrews, which embrace and bea-r against the sides of the second section, whieh cannot be.

braced insidb on account of the mold which is to be formed, therein, and which occupies 'the whole or nearly the whole depth, keeps them Yuoldis of unequal thickness on the two sides,

by means of the clampserews either ojf the `drag or the cope, orboth7 the cheek or second section of the ask can be moved laterally t0 make the two sidesof equal thickness, because that part ol" the mold which determines the foi- 1n ofthe inside ofthe vessel is Wholly corstructed with the drag or first section, and the* part which determines 4the form of the outside of the vessel is connected with thc checker second section, the sides of which can yield to the pressure of the clarnp-screws. Along 'the sides of the second section are secured vertical wings n, at given distances apart, which project inward to a sufficient distance to sus` tain the sand which is rammed in to l'orm the sides ofthe mold, and when required similar' wings are also attached to the inner surface of the ends;y but for cast-ing batlrtubs, as in the present example, to sustain that part of the end of the mold which determines the forni 0f the head end of the tub, which is a long` and gradual curve, the wings n project inward from a plate, p, attached to the sides near the end. These wings have been heretolore well known and employed for this purpose; but their upper edges have heretofore been mudo horizontal, and it frequently happens that the mold is destroyed by the caving in of the sides and ends. To remedy this evil the upper edges of these wings are cut down from the inner edge, as at q, so that the sand between the several wings shall be united over these curved edges and bind the whole to prevent the caving in. t

I do not wish to be understood as limiting myself to the number and the manner of maklng and connecting,` the braces which connect the sides of the drag and cope or irst andthird sections of the flask, nor to the number and form of the clamps, nor to the use of clampscrews; nor to the curvaturcof the upper edge of the Wings on the second section of the flask, as it will be obvious that these may be variously changed in forni and equivalent means substituted having the same inode of operation and producing like results.

` `What I claim as my invention, and desire to secure by Letters Patent, is

l. Connecting` by means of a brace 0r braces the sides of the drag or rst section and of the cope or third section of lasks for casting bath-tubs or other large and thin hollow vessels, substantially as described, in combination with the clamps and adjusting-screws or their equivalents which embrace and act upon the sides of the cheek or second section ol' the lask, substantially as and for the purpose l specified.

2. ltecessing the upper edge of the wings on the inside of the cheek or second section oi' the flask back ol the inner edge, substantially as and for the purpose specified.

JOHN DEMARILT. \Vitnesses:

XVM. ll. lhsn'on, ANDREW lh: Tina'. 

